There are known to be a number of moulded soles for shoes comprising resilient chambers located both on the upper surface of the sole so as to contact the insole underneath the foot and projecting downwards from the sole so as to act as a tread. Such chambers are indeed air chambers communicating with the inside of the shoe and allowing the foot to be more or less effectively ventilated during walking in order to oppose to the troublesome, not very hygienic perspiration of the foot. They also provide a more or less strong cushioning effect because of their deflection and expansion back to their original state during walking.
However, in spite of the several solutions brought forward the results are not very satisfactory since a greater rate of foot ventilation would be desirable, avoiding at the same time an excessive deflection of the air chambers which could give the user troubles. Moreover, there arises the need of an air circulation not only limited to the ejection and suction always of the same air but providing a real air change.
The present invention seeks to overcome the above problems and provides a shoe sole of the above-mentioned type in which the arrangement of the air chambers is not limited to the upper or lower side of the sole anymore but takes up the whole thickness of the sole, thus also ensuring an effective shock-resistant action against any soil unevenness on which the foot is laid besides enough ventilation to the benefit of the user's foot.
A second object of the present invention is to provide a sole of the above-mentioned type wherein the air chambers are provided with means capable of exerting a beneficial, tonic action causing the user's feet to be massaged in a more significant manner than heretofore known.
Still another object of the invention is to provide a particularly light, cost-effective shoe sole of simple, sturdy construction being affected by no problems caused by any of its mechanical parts and/or delicate components.
Finally, another object of the invention is to provide a shoe sole wherein the tread is capable of expelling any material stuck on it during walking.